Kahl S.,Sapa Technology
Flat rectangular profiles of the aluminium alloy AA6061-T6 were friction stir welded to butt joints. Welding parameters outside the process window generated a random mixture of good welds and welds with small voids. These voids approximately reduced the tensile strength by 10%, the ductility by half, and the fatigue strength by 20% as compared to void-free welds. Voids can easily be detected on fracture surfaces. Void-free specimens have approximately 10% lower fatigue strength if the fatigue crack extends over a corner of the specimen cross section as compared to a semi-elliptical fatigue crack. Source
Sapa Technology | Date: 2010-10-12
A method for making a sandwich material. A core layer of a first alloy is provided. The first alloy includes by wt. %: 0.5-2.0% Mn, 1.0% Mg, 0.2% Si, 0.3% Ti, 0.3% Cr, 0.3% Zr, 0.2% Cu, 3% Zn, 0.2% In, 0.1% Sn and 0.7% (Fe+Ni), the rest Al and 0.05% of each of unavoidable contaminants. A barrier layer of a second alloy is provided. The second alloy includes by wt. %: 0.2% Mn+Cr, 1.0% Mg, 1.6-5% Si, 0.3% Ti, 0.2% Zr, 0.2% Cu, 3% Zn, 0.2% In, 0.1% Sn and 1.5% (Fe+Ni), the rest Al and 0.05% of each of unavoidable contaminants. The core and barrier layers are rolled together so that they adhere and form a sandwich material. The sandwich material is heat treated so that the Si-content is equalized to 0.4-1% in the core and barrier layers. The sandwich material is rolled to a final thickness.
Sapa Technology | Date: 2010-05-14
An aluminium alloy brazing sheet comprising: a core material made of an aluminium alloy consisting of 0.1 wt % Si, most preferably 0.06 wt % Si, 0.35 wt % Mg, from 1.0 to 2.0 wt %, preferably 1.4 to 1.8 wt % Mn, from 0.2 to 1.0, preferably 0.6 to 1.0 wt % Cu, 0.7 wt % Fe, 0.3 wt % each of Zr, Ti, Ni, Hf, V, Cr, In, Sn and 0.5 wt % total of Zr, Ti, Ni, Hf, V, Cr, In, Sn, the remainder being Al and unavoidable impurities;
Sapa Technology | Date: 2010-09-17
A multi layered aluminum alloy brazing sheet including a core material, an intermediate layer on at least one side of the core material, the intermediate layer comprising an AlSi braze alloy, and a thin covering layer on top of the intermediate layer, The core material and the covering layer have a higher melting temperature than the AlSi braze alloy. The covering layer includes Bi 0.01 to 1.0 wt-%, Mg0.01 wt-%, Mn1.0 wt-%, Cu1.2 wt-%, Fe1.0 wt-%, Si4.0 wt-%, Ti0.1 wt-%, Zr, Cr, V and/or Sc in total 0.2%, and unavoidable impurities each in amounts less than 0.05 wt-%, and a total impurity content of less than 0.2 wt-%, the balance including aluminium. A heat exchanger including the alloy brazing sheet.
Sapa Technology | Date: 2010-05-12
An aluminium alloy brazing sheet including: a core material made of an aluminium alloy; and a cladding material clad on at least one side of the core material and made of an aluminium alloy having a potential lower than that of the core material. The cladding material is an outermost layer of the brazing sheet, wherein the cladding material is made of an aluminium alloy including 0.2 to 2.0 wt % of Mg, 0.5 to 1.5 wt % of Si, 1.0 to 2.0 wt %, preferably 1.4-1.8% of Mn, 0.7 wt % of Fe, 0.1 wt % of Cu, and 4 wt % of Zn, 0.3 wt % each of Zr, Ti, Ni, Hf, V, Cr, In, Sn and 0.5 wt % total of Zr, Ti, Ni, Hf, V, Cr, In, Sn, the remainder being Al and unavoidable impurities.